For those looking to maximize high boost pressure/high RPM performance in a 400 HP bolt-on platform, the Legacy GT TD06H-18G is for you. Utilizing a TD06 18G compressor wheel in a true TD06 compressor housing for maximum compressor efficiency, the TD06H-18G substitutes the larger TD06H high flow turbine in place of the TD05H turbine to maximize high RPM/high boost pressure exhaust flow while maintaining good throttle response.